The length of the ulna, radius, tibia, and fibula was measured in 220 normal fetuses. Computerized curve fitting provided normal values of bone length for age and biparietal diameter. Ratios of the length of the different bones are presented. Possible applications of these measurements include: in utero diagnosis of fetal dwarfism, limb malformations, microcephaly, determination of gestational age, archeological dating of fetuses, and forensic applications.